//- 继承模板
extends index.pug 

//- 块内容替换、插入（prepend：插入到前面。append：插入到后面）
//- 插入操作可以省略 block
block  scripts 
  script(src='/page-a.js')
  script(src='/pets.js')

block content 
  h1= title 
  - var pets = ['cat', 'dog', 'fish']
  each petName in pets 
    include pet.pug

block block
   p 替换
block prepend block 
   p 插入到前面
block append block
   p 插入到后面